Such release ski bindings are described in German Pat. No. 25 33 337. In these conventional ski bindings, the spring of the holding mechanism acts through a piston on a generally mushroom-shaped follower member which is swingably supported to all sides in the housing of the holding mechanism. The stem part of the mushroom-shaped follower member is received in a recess of a ski-fixed fitting. In these conventional ski bindings, the ski shoe is held at its tip by means of a rigid bar on the sole plate. In the case of a fall of the skier rearwardly, the ski shoe, therefore, is released only with great difficulty.
This disadvantage is avoided in the ski binding according to German Pat. No. 23 24 078; however, this binding is very complicated in its design, whereby the release mechanism is stored in the space between the base plate and the sole plate. This, however, requires special sealing measures to prevent the penetration of snow and dirt. Furthermore, mounting of this device is complicated and expensive.
The goal of the invention is to overcome the mentioned disadvantages of the conventional designs and to provide a release ski binding of the abovementioned type, which is simple in its design and inexpensive to manufacture and which opens also during rearward falls of the skier.
This goal is inventively attained primarily by the locking mechanism having holding elements in the form of two laterally spaced jaw pairs or of one laterally spaced jaw pair and one heel down-holding means, which holding elements are movable into the clamping position by a stepping bar which is supported on the sole plate and which is under the influence of an erecting spring.
A number of possibilities are offered for the concrete structural development of the inventive release ski binding. Thus, one inventive embodiment is distinguished primarily by the stepping bar being swingably supported in a housing on the sole plate and being coupled with a slide plate which is guided on the sole plate, which slide plate has four wedge-shaped shoulders engageable with the jaws for the purpose of moving same to the locking position. A hinge plate is provided for coupling the stepping bar with the slide plate, one end of which hinge plate is swingably supported on the slide plate and the other end is slidingly guided by means of a transversely extending bolt, the ends of which are received in a slotted hole of the stepping bar and on a cam surface arranged on the sole plate.
A further exemplary embodiment is inventively distinguished from the prior art by the stepping bar being supported through a hinge plate on a slide plate which is guided on the sole plate and which carries at its front end control elements, which are constructed as chucking wedges, for effecting an erecting of the two jaws and, in the rear region thereof, is connected to a two-arm lever for moving the heel down-holding means mounted on an articulated parallelogram. In a modification of this exemplary embodiment, the slide plate is replaced with a slide ring, and the jaws are not swung into the clamping position by wedges, but by a pressing rod and by pulling rods which are hinged to the slide ring. In both embodiments, it is possible to hinge the two-arm lever on a piston guided in a spring housing and is loaded on both sides by pressure springs. Further, the heel down-holding means can be held during the stepping-in operation by a locking lever, however, can be released at the end of the stepping-in operation. In this instance, the one pressure spring is supported on a piston which is secured to the slide plate or on the pressure rod. Furthermore, it is possible for the heel down-holding means to carry a locking nose, which is associated with the locking groove of a swingably supported stepping plate constructed as a locking lever.
These measures have the advantage that the heel of the ski boot is clamped in place only when it rests on the sole plate. An incorrectly skewed clamping of the ski shoe is therefore practically impossible.
In these embodiments, it is furthermore provided that the rod of the piston extends through the spring housing, and is supported on a portion of the holding mechanism. Further, the part of the slide plate or rather of the pressing rod, which part is extended beyond the spring housing, carries a hook, into which engages a locking pawl in the locked position of the slide plate, which locking pawl is loaded by a spring. In this manner, the movement of the jaw into the open position is started reliably by the holding mechanism.